[DD_lancer]

Hey,

I have been helping my little brother with his system in his BA XT falcon.

The system is as follows:

HU - Older panasonic 3 x 5v output (cant remember model?)
Speakers - Stock
Sub Amp - Eclipse XA1200 mono 600wrms at 2ohms
Sub - Eclipse SW6210 12" 500wrms DVC (in a small sealed box)

Now we have only recently upgraded the amp from an old fusion fe402 2ch amp to the one listed above, hooked it all up and the bass is nowhere near as good as it was with the old amp??? Checked everything gain, lp filter, bass boost and all set to normal levels but still very little bass?

The only thing I can think of is the speaker wire from the amp to sub is very thin gauge, could this have an effect on how its performing? Other then that I'm puzzled??

Any help or comments would be great!

Cheers

[Tobyrose12345]

Are you sure eveything is set correctly? Thats basically the only thing I can think of!

[DD_lancer]

Tobyrose12345, on 29 July 2010 - 12:47 PM, said:

Are you sure eveything is set correctly? Thats basically the only thing I can think of!

Yeah I checked it all again tonight.

Settings are:

AMP
Gain - about 1/2
lp filter - about 80-100
Bass boost - about 40

HU
Sub level + 4
lpf - 80
hpf - off

Does that all look ok?

[Damon]

Possible phase issue. Check the phase of the subwoofer compared to the main speakers. Also, you haven't inadvertently wired the dual voice coils to 'fight' each other have you?

[shiny_car]

DD_lancer, on 29 July 2010 - 10:44 PM, said:

Sub Amp - Eclipse XA1200 mono 600wrms at 2ohms
Sub - Eclipse SW6210 12" 500wrms DVC (in a small sealed box)

Now we have only recently upgraded the amp from an old fusion fe402 2ch amp to the one listed above, hooked it all up and the bass is nowhere near as good as it was with the old amp???

I presume the sub - being DVC - is 'dual 4ohm' (ie: each VC is 4ohm)? Can you confirm? Or is it dual 2ohm?

Just that, with the Fusion amp, you must have run it at 8ohm bridged (if D4), or 4ohm bridged (if D2).

With the monoblock, how is it wired up? 2/4/8ohm? That will obviously impact on how much power the amp can produce.

If both the HU and amp have a LP filter, use just one or the other, and keep it simple. If he was using teh HU's LP at 80Hz before, stick with that, and turn the amplifier's LP filter off (or set it really high, like at 200Hz which will make it ineffective).

Aside from the amp, I've interpreted your post to say that nothing else has changed: still the same car, same HU, same speakers, same sub/box, same box position in the boot. Just changed the amp - correct?

:)

[DD_lancer]

Damon, on 29 July 2010 - 09:44 PM, said:

Possible phase issue. Check the phase of the subwoofer compared to the main speakers. Also, you haven't inadvertently wired the dual voice coils to 'fight' each other have you?

What do u mean by phase??

Yeah thats a good point I might have inadvertently wired it back up wrong? Will have to check that out!

shiny_car, on 30 July 2010 - 01:59 AM, said:

I presume the sub - being DVC - is 'dual 4ohm' (ie: each VC is 4ohm)? Can you confirm? Or is it dual 2ohm?

Just that, with the Fusion amp, you must have run it at 8ohm bridged (if D4), or 4ohm bridged (if D2).

With the monoblock, how is it wired up? 2/4/8ohm? That will obviously impact on how much power the amp can produce.

If both the HU and amp have a LP filter, use just one or the other, and keep it simple. If he was using teh HU's LP at 80Hz before, stick with that, and turn the amplifier's LP filter off (or set it really high, like at 200Hz which will make it ineffective).

Aside from the amp, I've interpreted your post to say that nothing else has changed: still the same car, same HU, same speakers, same sub/box, same box position in the boot. Just changed the amp - correct?

:)

Yep dual 4ohm coils.

Yeah I used to run the amp bridged and sub wired to 2ohms, will that make the amp run at 8ohms if its not rated for 2ohm bridged?

When u say how is it wired up I thought you just wire the sub to what ohms you want the amp to run at?? Yes/no?

Ok will kill one of the LP filters, which do u think would be better? HU or amp?

Sorry its not exactly as it was before.... as we added the new amp we added the hu. The sub and amp used to run off the stock hu thru a hi level imput converter thing. Everything else is the same.

Another thing I thought of was its still running on 8ga power and earth, would upgrading to 4ga help. I didnt do it because I didnt think it would matter, plus he is only a uni student and $$$ are a little scarce.... :)

Thanks heaps!

[shiny_car]

DD_lancer, on 31 July 2010 - 07:52 PM, said:

What do u mean by phase??

Yeah thats a good point I might have inadvertently wired it back up wrong? Will have to check that out!

An example of phase is: instead of the cone moving 'in-out', you make it move 'out-in'. This is a 180 degree difference in phase.

If you were to play ONLY the sub, then it would probably sound exactly the same. But, you want to make the sub play in-phase with the front speakers as best as possible.

Without needing to measure or be technical about it, if you swap the polarity of the speaker wiring, it will change the phase by 180 degrees, which might bring the sub more in-phase with the speakers, to make things sound better.

So, you simply swap the POS and NEG speakerwires around, at EITHER the amplifier terminals OR the sub terminals, but not at both ends.

If you wired the two voicecoils out of phase with each other, you'd end up with virtually 'inaudible' bass. Literally, virtually nothing. I doubt this has occurred in your situation.

Quote

Yep dual 4ohm coils.

Yeah I used to run the amp bridged and sub wired to 2ohms, will that make the amp run at 8ohms if its not rated for 2ohm bridged?

When u say how is it wired up I thought you just wire the sub to what ohms you want the amp to run at?? Yes/no?

The sub or speaker determines what impedence (ohm) the amp operates at. If you connect up a 4ohm sub, the amp operates at 4ohm; if you connect up a 2ohm sub, it operates at 2ohm.

If your sub is dual 4ohm, it can only be wired to be 2ohm (VCs in parallel) or 8ohm (VCs in series). Not 4ohm.

The Fusions cannot operate at 2ohm bridged (without risk of overheating of shutting down). So I can only presume you have had the sub wired to be 8ohm, and the amp operating at 8ohm bridged.

With the Eclipse amp, you should rewire the sub to be 2ohm, and run the amp at 2ohm.

Quote

Ok will kill one of the LP filters, which do u think would be better? HU or amp?

Try only the HU.

Quote

Sorry its not exactly as it was before.... as we added the new amp we added the hu. The sub and amp used to run off the stock hu thru a hi level imput converter thing. Everything else is the same.

Cool. New HU should not make things any worse, but better, if anything.

Quote

Another thing I thought of was its still running on 8ga power and earth, would upgrading to 4ga help. I didnt do it because I didnt think it would matter

Should make a difference, particularly at lower volumes, where the 8awg will handle the current the amp would draw.

The Eclipse is very efficient, so 8awg is likely thick enough anyway.

:)

[DD_lancer]

shiny_car, on 31 July 2010 - 09:04 PM, said:

An example of phase is: instead of the cone moving 'in-out', you make it move 'out-in'. This is a 180 degree difference in phase.

If you were to play ONLY the sub, then it would probably sound exactly the same. But, you want to make the sub play in-phase with the front speakers as best as possible.

Without needing to measure or be technical about it, if you swap the polarity of the speaker wiring, it will change the phase by 180 degrees, which might bring the sub more in-phase with the speakers, to make things sound better.

So, you simply swap the POS and NEG speakerwires around, at EITHER the amplifier terminals OR the sub terminals, but not at both ends.

If you wired the two voicecoils out of phase with each other, you'd end up with virtually 'inaudible' bass. Literally, virtually nothing. I doubt this has occurred in your situation.

Ok sounds like I may have done this, so say at the amp end put the sub NEG into the amp POS and the sub POS into the amp NEG?? I have never heard of this before?? My alpine hu has a phase option on it so maybe thats why I have never has this issue?

With the sub it should be wired like this right? http://a248.e.akamai..._4-ohm_mono.jpg

Other then the above 2 possible issues you can't see any other major issues?

The amp specs are here if that helps at all? http://www.eclipse-w...amp/xa1200.html

Thanks again!

This post has been edited by DD_lancer: 01 August 2010 - 09:48 AM

[shiny_car]

Your wiring description is correct.

There shouldn't be any other issues. Except if the 'gain' simply isn't set high enough, but if you're in doubt about this, have an experienced installer have a look and listen.

:)

[DD_lancer]

DD_lancer, on 31 July 2010 - 11:40 PM, said:

Ok sounds like I may have done this, so say at the amp end put the sub NEG into the amp POS and the sub POS into the amp NEG??

So is this right? Do I leave it like this or just connect and then put back to normal?

shiny_car, on 01 August 2010 - 09:43 AM, said:

Your wiring description is correct.

There shouldn't be any other issues. Except if the 'gain' simply isn't set high enough, but if you're in doubt about this, have an experienced installer have a look and listen.

:)

Ok thanks again!

[shiny_car]

DD_lancer, on 01 August 2010 - 09:02 PM, said:

So is this right? Do I leave it like this or just connect and then put back to normal?

It's right. Try it, and compare with 'normal'. Use whichever sounds best; if there's no obvious difference, use either.

:)